Chocolate and its derivatives are a specific type of mixture in which sugar and cocoa solids are dispersed in a continuous phase constituted by cocoa butter.
It is known that the production of chocolate includes the operations of:
metering sugar, cocoa in paste or solid form, cocoa butter, powdered milk and other ingredients, PA1 mixing the ingredients to form a mixture, PA1 refining the mixture by reducing the particle dimensions, and PA1 conching.
Among these operations, conching is of fundamental importance and is absolutely critical with regard to the final quality of the chocolate. In fact conching, by removing a certain proportion of moisture and other volatile components, for example acetic acid, butyric acid, valeric acid and other components in the mixture enables the organoleptic characteristics of the chocolate to develop.
Up till now, the conching has been carried out by mechanical working of the mixture in metal conches in which a large quantity of refined chocolate mixture is mixed slowly and without interruption for about 24-80 hours at a temperature of between 40.degree. C. and 90.degree. C. according to the type of chocolate it is intended to produce.
One is dealing essentially with a discontinuous production method in which a large quantity of mechanical energy is transferred to the mixture.
For this purpose it is important to note that the more slowly this energy transfer occurs the better the organoleptic properties of the final product.
It has been shown (by A. G Lipscomb as cited by H. Fincke in "Handbuch der Kakaoerzeugnisse", page 225, second edition, Springer-Verlag, Berlin 1965) that, by extending the duration of the conching so as to expose the mixture to air for a longer time, the organoleptic characteristics of the final product are improved appreciably. This is due not only to the removal of a greater quantity of moisture and volatile components from the mixture but also to the oxidation of the solid particles which may occur in the mixture during the prolonged exposure to air while the fatty phase is protected by the presence of natural anti-oxidants.
Although, on the one hand, the prior art is able to provide a good chocolate, on the other hand it has the disadvantage that the refining and conching require machinery with a low productivity and high consumption of energy which do not make it convenient to prolong the conching excessively.
The problem at the basis of the present invention is that of devising a method for the production of a mixture of the type specified which enables all the problems mentioned above with reference to the prior art to be overcome and which enables the organoleptic characteristics of the finished product to be improved appreciably.